1. Field of the Invention
This invention relates to a new and improved removable orthodontic appliance, namely, a tooth repositioning appliance and method. The present invention expands the range of treatments for minor malocclusions by allowing the orthodontist to shift the position of the teeth within the upper or lower arch a greater distance and also to move one dental arch relative to the other. Deep overbites or open bites may also be corrected. The invention enables the orthodontist to treat more severely malposed teeth than is possible with prior removable orthodontic "finishing" appliances. A feature of the invention is the fact that it is removable and the patient himself can remove and replace the appliances.
2. Description Of Related Art
Removable orthodontic appliances are old in the art as are two piece appliances. U.S. Pat. No. 4,505,672 discloses upper and lower appliances for the upper and lower jaws and mechanical clasps and/or suction cups to attach the appliances to the teeth. Resilient means interconnect the two appliances. The present invention differs from the disclosure of such patent in a number of respects, one being that the use of clasps that grip between the teeth frequently opening up a gap between teeth is not employed. The present invention uses clasp assemblies which firmly grip individual teeth. The guides and guideways in such reference limit the effectiveness of the positioner; a feature of the present invention is that such guides and guideways are not required.
Single piece appliances which fit on both the upper and lower jaw are shown in patents to Kesling, such as U.S. Pat. Nos. 4,330,273; 4,195,046; 3,837,081; 3,724,075; and 3,178,820. See also, Practical Application of the Kesling Tooth Positioner by Peter C. Kesling, D.D.S. Positioners of this type are formed of an elastic material about the arches in a slightly open position. The elasticity of the material in the positioners puts pressure on the teeth biasing them from their present position to the new, ideal position as the appliance is seated. Single piece appliances suffer from the severe limitation that when the patient's jaw muscles are relaxed, the device is not effective. One of the features of the present invention is the fact that there are two separate positioners, one for the upper and one for the lower jaw and each positioner locks onto the undercuts of the teeth, whether natural or enhanced by bonded additions.
In the main, other tooth positioning appliances heretofore used in the orthodonture profession have been permanent appliances which are adjusted from time to time by the orthodontist but otherwise remain fixed to the teeth. A feature of the present invention is the fact that the device may be removed as required and particularly when the patient is speaking. Nevertheless, the appliances may be worn while sleeping without undue discomfort.